Typical neural adaptation for familiar images in autistic adolescents

Abstract

It has been proposed that autistic perception may be marked by a reduced influence of temporal context. Under this hypothesis, prior exposure to a stimulus should lead to a weaker or absent alteration of the behavioral and neural response to the stimulus in autism, compared to a typical population. To examine this hypothesis, we recruited two samples of human volunteers: a student sample (N=26), which we used to establish our analysis pipeline, and an adolescent sample (N=36), which consisted of a group of autistic (N=18) and a group of non-autistic (N=18) participants. All participants were presented with visual stimulus streams consisting of novel and familiar image pairs, while they attentively monitored each stream. We recorded task performance and used magnetoencephalography (MEG) to measure neural responses, and to compare the responses to familiar and novel images. We found behavioral facilitation as well as a reduction of event-related field (ERF) amplitude for familiar, compared to novel, images in both samples. Crucially, we found statistical evidence against between-group effects of familiarity on both behavioral and neural responses in the adolescent sample, suggesting that the influence of familiarity is comparable between autistic and non-autistic adolescents. These findings challenge the notion that perception in autism is marked by a reduced influence of prior exposure.